[spinal nerve] n (ca. 1793): any of the paired nerves which leave the spinal cord of a craniate vertebrate, supply muscles of the trunk and limbs, and connect with the nerves of the sympathetic nervous system, which arise by a short motor ventral root and a short sensory dorsal root, and of which there are 31 pairs in humans classified according to the part of the spinal cord from which they arise into
8. cervical pairs, 12 thoracic pairs,
5. lumbar pairs,
5. sacral pairs, and one coccygeal pair